This invention relates to ceramic articles and to methods of making same. More particularly, the invention relates to tantalum carbide articles and to methods of making same.
There has long been a need for refractory materials capable of use in high temperature environments. Most recently, refractory materials have been developed for space applications. Typically, materials have been developed for throat areas of solid propellant rocket nozzles. These throat areas are subject not only to high temperatures and pressures but to severe thermal shock, to mechanical erosion, and to chemical erosion. Materials developed in the past for this application include graphite, tungsten, alumina, zirconia, and hafnia. However, each of these materials lacks resistance to one or more of the above areas of degradation. Zirconia, hafnia and graphite, which having excellent thermal shock resistance, has poor chemical and mechanical erosion resistance. Tungsten is heavy, hard to fabricate, and has poor chemical erosion resistance. Alumina, on the other hand has poor thermal shock resistance. Applicants' prior invention disclosed in U.S. Pat. No. 3,706,583, while adequate for the purposes intended, did not provide the improved thermal, mechanical and chemical erosion resistance as the present invention disclosed and claimed herein.
It is therefore an object of the present invention to provide an improved ceramic article having high thermal shock resistance. It is a further object to produce such an article having good mechanical and chemical erosion resistance at elevated temperatures. It is still a further object to provide such an article including tantalum carbide.